Marie Mills holds a picture of her father, Medric Cecil Mills, at the home of a neighbor on Wednesday in Washington. (Jahi Chikwendiu/The Washington Post)

A D.C. fire lieutenant and a firefighter were put on administrative leave Thursday as city authorities investigate why a man who suffered a fatal heart attack outside a Northeast Washington firehouse didn’t get care, according to officials familiar with the case.

The move comes one day after the lieutenant — identified by District officials as Kellene Davis — met with the fire department’s internal affairs division. Officials declined to say what Davis, 51, said at the meeting, and she could not be reached for comment.

But in a letter to city Fire Chief Kenneth B. Ellerbe, Davis, a 28-year veteran, said a firefighter told her that someone had slipped and fallen across the street. She said she told the firefighter to get an address and that she would go help. But she said he never returned with the address and instead told her that an ambulance had already been dispatched. It was unclear whether that firefighter is the one who was placed on administrative leave.

A fire department spokesman confirmed that the letter was sent to the chief by Davis. It was first reported by WTTG (Channel 5) on Thursday.

No action has been taken against a probationary firefighter who told people who sought help for the dying man that they had to call 911 before anyone could respond, although Davis said in her letter to the chief that she reprimanded that firefighter for not ringing the station alarm. Officials said that the firefighter properly told the lieutenant that people were seeking help and that the investigation now centers on why nothing was apparently done. Three fire department officials said that the probationary firefighter was moved to Truck 11, near Brightwood Park, and responded to a fire Wednesday night.

The fatal incident occurred Saturday when 77-year-old Medric Cecil Mills Jr., who had worked for the District more than four decades, collapsed outside a computer store at a strip mall across the street from the fire station on Rhode Island Avenue in the Brookland neighborhood.

His daughter, Marie Mills, said bystanders called 911 but also rushed to the station and banged on the door seeking help. But Mills said a firefighter told them that no one could respond until someone called 911 and they were dispatched. “There’s nothing I can do if my lieutenant doesn’t tell me to go,” he reportedly said, according to Marie Mills.

She said that a D.C. police officer flagged down a passing ambulance and that her father was treated about 15 minutes after he collapsed. He died later that afternoon at MedStar Washington Hospital Center.

The incident and subsequent inquiry come as the city investigates another case in which a man died after receiving questionable care, city officials said. That incident occurred Jan. 10 on 16th Street NW when 39-year-old Jose Santos Ruiz Perez collapsed in front of his apartment.

D.C. Council member Jim Graham (D-Ward 1) said Perez’s relatives and authorities told him that a District police officer waved off an ambulance heading toward Perez, who had been drinking. Graham said the officer woke Perez, escorted him into his apartment and put him on a couch and left. A relative found Ruiz dead five hours later, according to a D.C. police report. A cause of death has not been determined.

But fire officials offered a different version. Those officials said two firefighters evaluated Ruiz, who declined treatment, but failed to obtain the required forms relinquishing them of responsibility before leaving. There is no fire or police report on the first encounter. A District official said the matter remains under investigation.

In the Mills case, District officials, including the mayor, reached out to the family and called the case an unacceptable breach of the public trust. “There are no regulations or protocols that would have prevented [fire department] personnel on the scene from taking action to help Mr. Mills,” Paul A. Quander Jr., deputy mayor for public safety, said in a statement Thursday. “It’s hard to get your arms around how and why this happened.”